Generally known dosage forms for oral solid preparations include tablets, capsules, granules and powders. However, these dosage forms are largely hard to handle and ingest. For example, tablets and capsules have a problem in that larger ones are harder to swallow, and granules and powders also have a problem in that they are easy to choke on and likely to get stuck between the teeth upon their ingestion. In addition, these dosage forms need to be taken with some water, and thus have difficulty in ingestion in the case of an emergency and for bedridden patients with severe illness.
Known dosage forms that can be taken without water include chewable tablets, which are designed to be ingested by chewing. Currently available chewable tablets have poor disintegrability and thus are hard to take for elderly people, children, preschool children, patients with dysphagia, bedridden patients and others.
Under such circumstances, there is a desire for the development of orally fast disintegrating tablets which can be easily taken without water and can be conveniently taken anytime and anywhere.
Known techniques for producing such orally fast disintegrating tablets include a method involving filling a mold (resin film sheet for PTP) with a suspension of an active ingredient and a saccharide in an aqueous agar solution, and solidifying the suspension into a jelly-like form, followed by reduced pressure drying or aeration drying (Patent Literature 1); and a method involving compressing tablet materials in a dry state containing a pharmaceutical agent, a water soluble binder and a water soluble excipient with a minimum pressure necessary for formation of tablets having a hardness enough to keep their shapes during the transition to the next step, wetting the resulting tablets, and drying the wet tablets (Patent Literature 2).
However, these methods are disadvantageous because they require special production equipment and thus are complicated as a production process.
Under such circumstances, there is a desire for the development of preparations that are producible by a simple process with simple production equipment, excellent in oral disintegrability, and practically satisfactory in moldability.